The present invention relates to an imaging apparatus, and specifically the present invention relates to an imaging apparatus having an exhaust section which exhausts air used by a cooling section for cooling a projection section to the outside of an exterior cabinet.
A cooling device for a conventional projection-type imaging apparatus will now be described with reference to the drawings.
In reference to FIGS. 21 and 22, a projection-type imaging apparatus 2100 includes a projection section 2202 for projecting an image onto a screen, a cooling section 2203 for cooling the projection section 2202 using air, and an exterior cabinet 1 for housing the projection section 2202 and the cooling section 2203. The projection section 2202 includes a light source-lamp unit 7, a mirror box 31, an emission optical unit 9, an imaging element unit 10, a projection lens unit 2201, a circuit unit 13, a power supply unit 14, and a light source lamp power supply unit 15. The cooling section 2203 includes a lamp cooling fan 19, a mirror cooling fan 20, a first cooling fan 16, a second cooling fan 17, and a third cooling fan 18.
The light source lamp unit 7 includes a light source lamp 5 and an oval reflection mirror 6. The projection lens unit 2201 includes a projection lens 12 and a lens moving device 11. The mirror box 31 includes a reflection mirror 8.
The exterior cabinet 1 has a front cabinet 21, a first side cabinet 22, a second side cabinet 23, a rear cabinet 24, an upper cabinet 25 and a lower cabinet 26. The front cabinet 21 has a first air intake 2, the first side cabinet 22 has a. second air intake 3, the second side cabinet 23 has a third air intake 27, and the upper cabinet 25 has an exhaust port 4. The rear cabinet 24 has a first exhaust port 28, a second exhaust port 29, and a third exhaust port 30.
The exterior cabinet 1 is formed of metal or resin, and has a six-faceted structure. The first intake 2 and the second intake 3 take in air, with which the cooling section 2203 cools down the projection section 2202, from outside the cabinet 1. The exhaust port 4 and the first to third exhaust ports 28 to 30 exhaust air which the cooling section 2203 has used for cooling, to the outside of the cabinet 1. As shown by arrows 2101 to 2105, the noise caused by the cooling section 2203 leaks to the outside of the cabinet 1, from the first air intake 2, the second air intake 3, the exhaust port 4, and the exhaust ports 28 to 30.
As the light source lamp 5, a xenon lamp or the like is used for a large output. The light emitted from the light source lamp 5 is reflected against the oval reflection mirror 6, and is optically reflected by the reflection mirror 8, thereby guided to the emission optical unit 9. The emission optical unit 9 is comprised of a condenser lens (not shown) and the like, for guiding light effectively to the imaging element unit 10. The imaging element unit 10 is a light valve for optically modulating image signals, and is a transmission type element such as liquid crystal or a reflection type element comprised of micro mirrors, etc., so as to generate optical picture information using light from the emission optical unit 9.
The optical picture information from the imaging element unit 10 is enlarged and projected through the projection lens 12. The projection lens 12 is capable of moving upward, downward, rightward, and leftward, by means of the lens moving device 11, for focus adjustments and angle of view adjustments.
The circuit unit 13 controls the imaging element unit 10. The power supply unit 14 drives the circuit unit 13 and the like. The light source lamp power supply unit 15 starts the light source lamp 5. The first cooling fan 16, the second cooling fan 17, and the third cooling fan 18 cool down the circuit unit 13, the power supply unit 14, and the light source lamp power supply unit 15, respectively.
The large-size lamp cooling fan 19 cools down the light source lamp 5. The mirror cooling fan 20 cools down the emission optical unit 9.
The first air intake 2 provided on the front cabinet 21, the second air intake 3 provided on the first side cabinet 22, and the third air intake 27 provided on the second side cabinet 23 take in exterior air as indicated by arrows 2204, 2205, and 2206. The first exhaust port 28 provided on the rear cabinet 24 exhausts air used for the cooling of the light source lamp power supply unit 15 as indicated by an arrow 2207. The second exhaust port 29 exhausts air used for the cooling of the light source lamp box 7 as indicated by an arrow 2208. The third exhaust port 30 exhausts air used for the cooling of the emission optical unit 9, from the mirror box 31 as indicated by an arrow 2209.
In order to obtain an image with a higher luminance, it is necessary to employ a light source lamp unit 7 and a light source lamp power supply unit 15 having a greater output. With such a structure, the quantity of the generated heat increases as the output increases, and therefore it is necessary to employ a large cooling fan so as to improve the cooling performance. Using a large cooling fan, however, results in a problem of increasing the cooling noise.
Furthermore, the use of projection-type imaging apparatuses is not only for presentations in conference rooms and the like but also includes viewing of images in halls, and therefore the market expects viewing of high quality images in quieter environments. With the structure described with reference to FIGS. 21 and 22, in which the air intakes 2, 3, and 27 are provided on the cabinet 1 so as to take in air, the noise of the cooling fans 16, 17, 18, 19, and 20 cutting the air is naturally radiated from the air intakes 2, 3, and 27, which results in a problem of increasing the noise from the imaging apparatus 2100.
In addition, the light emitted from the light source lamp 5 leaks outside the cabinet 1 from the air intakes 2, 3, and 27. This particularly poses a problem of not being able to obtain a high quality image when the image is projected in a dark environment such as in a movie theater, since the leaked light illuminates places other than the screen, which leads to not only worsening of the image viewing atmosphere but also deterioration of the image quality.
One object of the present invention is to provide an imaging apparatus which is capable of controlling emission of the noise caused by the cooling section so as to suppress the noise leaving the device, even in the case where a large cooling section is used for cooling a projection section with a high output needed for obtaining by images with higher luminance.
Another object of the present invention is to provide an imaging apparatus which is capable of preventing light emitted from the light source lamp unit from illuminating places other than the screen.
According to one aspect of the invention, an imaging apparatus includes: a projection section for projecting an image onto a screen; a cooling section for cooling the projection section by means of air; an exterior cabinet for housing the projection section and the cooling section; and an exhaust section for exhausting air used for the cooling of the projection section by the cooling section, from the exterior cabinet wherein the exhaust section has a function for attenuating a noise caused by the cooling section.
The exhaust section may include an exhaust duct having a ventilation path for guiding the noise and air from the projection section to the exterior of the exterior cabinet; and the ventilation path is formed so that the noise strikes an interior surface of the ventilation path and changes its direction of movement.
The ventilation path may be formed so that the moving path of the noise contains at least one L shape.
The exhaust duct may include a sound absorption material which is provided on the interior surf ace of the ventilation path for absorbing the noise.
The exterior cabinet may have a rear face which is formed on a side opposite to the screen; the exhaust duct may be provided on the location corresponding to the rear face; and the exhaust duct may exhaust air in a direction which is opposite to the direction in which the projection section projects the image onto the screen.
The exhaust duct may exhaust the air in a direction which is substantially the same as the direction in which the projection section projects the image onto the screen.
The exhaust duct may include at least one active muffling device provided in the ventilation path.
The projection section may include a light source lamp unit, an emission optical unit for collecting light from the light source lamp unit, an imaging element unit for generating optical picture information using light collected by the emission optical unit, and a projection lens unit for enlarging and projecting the optical picture information; and the cooling section may include a lamp cooling fan for cooling the light source lamp cooling unit, and a mirror cooling fan for cooling the emission optical unit.
The projection section may further include a circuit unit for controlling the imaging element unit, a power supply unit for driving the circuit unit; and a light source lamp power supply unit for driving the light source lamp unit; and the cooling section may further include a first cooling fan for cooling the circuit unit, a second cooling fan for cooling the power supply unit, and a third cooling fan for cooling the light source lamp power supply unit.
The cooling section may include a cooling fan.
The imaging apparatus may further include an air v intake section for taking in air from outside the exterior cabinet and providing air to the cooling section.
The air intake section may include an air intake duct for guiding air from the exterior of the exterior cabinet to the cooling section and for guiding the noise from the projection section to the exterior of the exterior cabinet; and the ventilation path may be formed so that the noise strikes an interior surface of the ventilation path and changes its direction of movement.
The ventilation path may be formed so that the moving path of the noise has at least one L shape.
The air intake duct may include a sound absorption material which is provided on the interior surface of the ventilation path for absorbing the noise.
The air intake duct may be provided at a position corresponding to the lower face of the exterior cabinet.
The air intake duct may include at least one active muffling device provided in the ventilation path.
The exterior cabinet may include a sound absorption material which is provided on at least one of interior surfaces of the exterior cabinet for absorbing the noise.
The projection section may include a light source lamp unit, an emission optical unit for collecting light from the light source lamp unit, an imaging element unit for generating optical picture information using light collected by the emission optical unit, and a projection lens unit for enlarging and projecting the optical picture information; the projection lens unit may include a projection lens and a projection lens moving device for moving the projection lens; and the exterior cabinet may have a front face which is formed at the side of the screen, the exterior cabinet further including a dust-proofing section which is provided between the front face and the projection lens moving device, for preventing outside dust from entering the apparatus; wherein the dust-proofing section includes at least two pieces of cloth, and a sound absorbing material inserted between the two pieces of cloth.
The imaging apparatus may be a projection-type imaging apparatus.
The imaging apparatus may be a liquid crystal projector.
The imaging apparatus may be a rear-projection television.